The physical damage thresholds of various mechanically sensitive electronic components, such as computer hard drives, are extremely low. Prior art suspension systems have attempted to address the need for vibration isolation in a mobile environment by using either a damper-mass or spring-mass based isolation system. However, damper-mass based isolation systems have significant mechanical coupling of vibrations above the system fundamental resonant frequency, resulting in poor high frequency vibration attenuation. Furthermore, spring-mass based systems do not limit or dampen vibrations at or near the fundamental system resonant frequency. The resulting amplitude of the mechanical displacement of spring-mass based systems can become very large at the system's major resonant frequency as a result of this resonant amplification.
The ratio of input vibration compared to the measured vibration of the isolated component is referred to as the systems transmissibility function. The system's transmissibility function, including the resonant amplification and the overall performance of a vibration isolation system can be evaluated by a swept sine wave stimulus function vibration source. Peak transmissibilities for a spring-mass based vibration isolation system can often exceed values of 20, and transmissibility factors of 200 or more have been measured. As such, neither damper-mass nor spring-mass based vibration isolation systems are suitable for general mobile vehicle applications.
There is a need for a vibration isolation system, which adequately protects these sensitive devices in a mobile vehicle environment. It is an object of the present invention to provide an inexpensive, simple, and durable shock and vibration isolation system for mechanically sensitive electronic components that is capable of performing well in a mobile vehicle environment. It is a further object of the present invention to provide a shock and vibration isolation system which enables the mechanically sensitive electronic components to be shipped, stored or mounted in any orientation.